This invention relates to a new and distinctive mandarin cultivar designated ‘FairchildLS’, which was developed at Riverside, Calif. and derived from an irradiated bud of ‘Fairchild’ mandarin. ‘Fairchild’ mandarin was produced by J. R. Furr in Indio, Calif. from a conventional hybridization of 2n Clementine ‘Algerian’ mandarin×2n ‘Orlando’ tangelo (itself a hybrid of ‘Duncan’ grapefruit×‘Dancy’ mandarin produced in Florida). ‘Fairchild’ was released in 1964.
Irradiation of budwood of ‘Fairchild’ mandarin, taken from registered trees in Lindcove, Calif., was accomplished in June, 1997 at Riverside using 50 Gray units of gamma irradiation from a Cobalt-60 irradiation source. Buds from this irradiation were propagated onto various rootstocks in the greenhouse at Riverside where they were grown to field-plantable-sized trees. These trees were planted in June 1998 at Riverside. Fruit production and evaluation on these trees began in 2001. One selection from this irradiated population (propagated on Carrizo citrange rootstock) distinguished itself from the others in having very low seed counts in comparison to the original ‘Fairchild’ cultivar, as well as having the excellent fruit quality and normal fruit production characteristics of the ‘Fairchild’ parent (see, FIGS. 1 and 2). This selection, later designated ‘FairchildLS’, was known throughout experimental evaluation as ‘Fairchild’ IR2 (for ‘Fairchild’ IRradiated selection #2). After two seasons of fruiting this selection, ‘Fairchild IR2’, was selected for further trials and in June 2002, buds were taken from this selection and propagated onto Carrizo and C35 citrange rootstocks at Riverside. In April 2003 budwood from this selection was sent to Riverside, Calif. for evaluation of disease status and elimination of viruses and other pathogens, as needed. Twenty trees, propagated from budwood taken from the “mother” tree selection were planted at Riverside in June 2003. Fruit production on these twenty trees commenced in 2006. In June 2005 two trees of ‘FairchildLS’, which had been produced from budwood tested and certified as tristeza-free, were sent to Lindcove, Calif. where they were planted in the citrus breeding block. Further propagations from the Riverside budwood source were made at Lindcove in the summer of 2003. In June 2004, twelve trees from this propagation were planted in Irvine, Calif. and two trees in Santa Paula, Calif. An additional forty-eight trees from this same 2003 propagation were planted in 2005 at four trial sites: Lindcove, Arvin, Oasis and Woodlake. All trials were propagated equally on Carrizo and C35 citrange rootstocks. Fruit production of these propagated trees commenced in 2006 (a few trees at two sites) and 2007 (most trees at most sites). The properties of ‘FairchildLS’ were found to be true to type and transmissible by asexual reproduction in comparing these plantings with the original ‘FairchildLS’ selection.